Machine for coating back seams of shoe uppers



. O. CHAPLIN ET AL June 15, 1954 MACHINE FOR COATING BACK SEAMS OF SHOE UPPERS Filed April 22, 1952 2 Sheets-Sheet 1 June 15, 1954 H. o. CHAPLIN ETAL 2,681,037

MACHINE FOR COATING BACK SEAMS OF SHOE UPPERS Filed April 22, .1952 2 Sheets-Sheet 2 F. Z 65 20 56' I 42 4 Fig OhHW ICHUJU.

0 W D V G 0 4 M :6 vr i fl 3 A J 1 Q00 HC.

Patented June 15, 1954 UNITED STATES PATENT OFFICE MACHINE FOR COATING BACK SEAMS OF SHOE UPPERS Application April 22, 1952, Serial No. 283,702

Claims priority, application Great Britain May 8, 1951 Claims. 1

This invention relates to back-seam-strengthening machines of the type in which a thermoplastic material is extruded upon the seam.

The reinforcement or strengthening of back seams has been commonly carried out by the application of a reinforcing tape secured to the back seam by adhesive. Such machines, in view of the curved characteristic of the upper at the back seam, are necessarily complicated and expensive. It has, however, been suggested in Letters Patent of the United States No. 2,325,656, granted August 3, 1943 on the application of John J. Brophy, that the back seam may be strengthened by coating the inturned edges of the upper with an adhesive material such as a thermoplastic resin which will harden and become nontacky, flexible and tough.

Accordingly, an object of the invention is to provide an improved machine for applying a coating material to the projecting back-seam ribs of shoe uppers which shall be quicker to operate and which will give more effective results.

It is well understood that closed uppers are more readily handled if they can be kept in a right-side-out condition although it is evident that this requires the application of the coating material to the projecting seam parts which lie upon the inside of the upper. One feature of the invention resides in an improved arrangement, facilitating this manner of handling, which in its illustrated form comprises a work-supporting post having an extruding outlet at its upper end so that the seams may be guided over the post in rightside-out condition as the material is applied thereto.

Other features of the invention lie in the provision of suitable guides or dams to prevent overflow of the material issuing from the outlet and in the utilization of a heated spreader, the temperature of which is very much higher than that of the post, for eiiecting a deeper penetration of the material and for removing any surplus from the inner surface of the upper. The illustrated machine also embodies a control valve by means of which the operator may regulate the out-flow of cement from the opening at the top of the supporting post and a feed roll positioned for engagement with the outside of the upper just above that post.

These and other features of the invention will best be understood from a consideration of the following specification taken in connection with the accompanying drawings in which Fig. 1 is a side elevation of the complete machine;

Fig. 2 is a vertical section through the Work suppporting post;

Fig, 3 is a plan view of the top of this post on an enlarged scale; and

Fig. 4 shows an enlarged view from the front of the machine illustrating the contours of the work, a feed roll, a crease guide and the work supporting post.

The illustrative machine comprises a base l0 carried at the top of a supporting column i2, this base being combined with a box-like frame [4 in which there is supported a receptacle it having a supply of coating material which is introduced therein by removing a cover [8. Inside this receptacle the material is melted by heat from an electric unit 29 which, for one illustrative material, heats it to about 270 F. The material is removed from this receptacle by means of a gear pump 22 connected by a conduit 24 to passages within a work supporting post 26. This post has at its upper end a seam receiving groove 28 in which there is an outlet opening 30 (Fig. 3).

The pump is driven by means of a chain 32 connecting it to a drive shaft 34 on which there is a pulley 36 connected by a belt 38 to a source of power such as an electric motor (not shown). The pressure at the delivery outlet of the pump is controlled by means of a by-pass 40 having in it a spring-pressed valve the action of which may be regulated by turning a screw 42. It will be seen that the conduit 24 is contained within a box-like structure 44 providing an oil bath kept at a temperature of about 315 F. by means of heating units 46. The front end of the chamber is closed by a plate 48 in which the conduit 24 is sealed and to which the post 26 is attached by means of bolts 50.

The post 26 (Fig. 2) has a large bore 52 in which there is positioned a valve rod 54 having a shouldered tip 56 adapted to enter and close the outlet 30. This rod which is normally held up in closed position by means of a spring 58 is guided in a threaded bushing 59 against which one end of the spring rests. The upper end of the spring presses against a gland packing 62 which is associated with the underside of an enlarged portion 54 of the rod so that the adhesive material cannot escape into the portion of the bore containing the spring. The upper end of the valve rod is fluted at 66 and slides in a reduced bore 68 which has at its upper end a shoulder 7!] cooperating with a shoulder at the top of the valve rod.

The post also has a supplemental passage 12 to which the melted material is admitted through an opening 14 positioned in alinement with the end of the conduit 24. The upper end of this :a chain 138 "from the mainshaftzu.

go up the sides or" the seam-forming rib ilfiof a shoe upper 82 (Fig. 4).

The outer end of the rib-receiving groove "28 is dammed by a depressible :gate 8'4 having a groove 85 shallower than the groove28 and which is mounted for sliding movement on the front of the post by means of a holding plate 86 in back of which there is a spring-88. The-upand down movement of this gate is restricted by means of a pin $0 passing through a slot 92 in the plate. It will be noted that the upper end ofthe gate is rounded as shown in Fig. 4, it being depressible -by'the pressure of a shoe upper passed thereover.

After the rib formed by the seam parts '85 has passed over the top of the post 25 it is received in a groove 9d extending along the top of a spreader block 95. This block, which is supported I by a bracket 98 attached to the cover-of the oil chamber id, is provided with an electric heater Hill by which its temperature may be raised to some 389 F. This temperature maybe regulated 'by suitable control devices (not shown) and it will be noted that the spreader block is connected to the post '23 by only a very shallow neck I82 to the end that there shall be a minimum loss of heat by conduction from the spreader block to the post 25. supporting bracket by a sheet IIM of insulating material. The higher temperature of the spreader block'Qt causes the plastic to he momentarily more fluid and enables the plastic to be forced into the stitches or the seam as "the'work is pressed down against the block. Since the groove 9A is shallower than the groove .23, spreader block 96 acts also as a scraper to remove surplusmaterial and as a dam to prevent accidental escape of the lhe block is also separated from its ISI) material at the inner end of the groove 28. One

suitable and convenient thermoplastic material for this purpose is, for example, a mixture of high molecular weight polyvinyl acetate, wood rosin and 'plasticizer. It will be understood that the Above the post 23 there is rotatably supported a rubber feed roll 6 it having a contour (Fig. 4) 'similar to that of the upper end of the'post and the gate '84, this roll being driven in the direction of the arrow in Fig. 1 so that when it is pressed against thework the latterwill be carried along the groove 28 over the outlet opening 36 and through the grooveQ of the spreader block. This :feed roll tilt is journaled'iniplates'l I2 (Fig. 1) carried at the end of a lever H l'pivoted upon a rod I It carried in a bracket 1 I8 attachedto'the "top of the frame It.

Attached to and journaled in the outer end of this lever I'M is a pulley 20 having a drive connection to the feed'roll through a series of pinions 122, I25, and "I26. The pulley is driven from the main shaft 34 bymeans of a :crossed'belt leading to a smaller pulley. I 28 on the rod HE and this pulley I28 is driven by means of Inasmuch as the pulley I28 is coaxial with the pivot rod I I6, the drive is unafiE-ected by the tilting of the lever l 4.

The tilting movements of lever H4 may be effected by means of a rod I32 joined to a lever I34 .mounted near the baseof .theframe on.a rod I36 supported.intbrackets' I38 attached to the frame. The forward end of this lever I34 has a reduced .portion I40 adapted to be brought into engagement with an adjustable abutment I52 threaded Ito and docked-upon a depending portion of the valve rod 56. The lever I34 is joined to a treadle (notshown) by a rod Hi4. It will also be noted 'thatthelupper endof the connecting rod I32 slides through the lever I I l but is surrounded by a :spring I45 resting against a collar I 38 and held under, pressure by a stop nut I53. Thus when the treadle is depressed the feed roll HE! is brought yieldingly intoengagement with the outside of an upper 82 (Fig. 4) and the valve rod s4 is depressed to open the outlet 36 at the top of the post. A "seam-"crease guide I52 is carried by plates H2 at the forward end of the:lever I I 4 and this guide is tapered at 1354 (Fig. 4) so'as better to fit inthe "crease'of the upper.

rib'tfl will pass along the shallower groove 9'3 of the spreader 96 which serves 'both as a .dam at 'the-rear'endotthe groove 28 and as a scraper to removezsurplus material from the seam :rib. passing ;over'thespreaderbIocl; 36 the tempera- 'ture of the material is momentarily :raised to 'a fsubstantialextent andthus the material-is made m'orezfiuid so thatit penetrates the stitches of the seam and sometimes the leather thereof. The spreader blockserves alsoto' iron-the material into the seam and-contacts the sides thereof. As'the .result of the characteristics of the material employe'dzit quickly hardens after thework is removedfromthe machine and effects a strengthening and reinforcing. of'the back seam.

.Havingthus "described-our inventiomwhat we claim'as 'new'and desire to secure byLetters Pat- 'ent of the United States is 1. :In :a machine for coating the back-seam "rib of ashoe upper, a-support having an outlet .opening'and'upon which. an upper may be positioned in right-side-out relation, rib-guiding means to aline'therib with said opening, driven -means:f'or'movingsaid upper over said support in thedirection of the heel seam, means for extruding aicoating material through said'opening, 'an'd spreader means over which the work passes .zforre'ducingthe viscosity or'the extruded mate- =rialbeyond thepoint of application so that it will penetrate the seam.

:2. In 'a machine for coating the "back-seam :rib'of a-shoe upper with a thermoactive adhesive material, a support narrower than an upper having'an outlet opening narrower than said rib and zuponwhich an upper may be positioned in rightside-outzrelation with the edge of a rib closing said: opening, driven means resting on said upper over "said support to move it in the direction of the heel seam,'means for heating the thermo- ;active adhesive material, means for extruding said material through said opening, and heated means engaging thecoated .ribior reducing the viscosity of the material which ,rhas been extruded upon the work thereby the more effectively to spread the material thereon.

3. In a machine for coating the back seam of a shoe upper, a work support provided with an outlet opening upon which a back seam may be supported in right-side-out relation, movably mounted means for supporting a feed roll for engagement with the outside of the upper adjacent to the back seam, a seam crease guide on said movably mounted roll support, extruding means supplying coating material to said outlet, an outlet valve, and operator-controlled means for moving the feed roll into engagement with the upper and opening said outlet valve.

4. In a machine for coating the projecting back seam of a shoe upper, a post the upper portion of which is provided with a transverse seam-receiving groove intersecting the front and rear faces of said post, means for extruding a coating material into said groove for application to the seam, and devices having shallower grooves positioned at either end of said groove for preventing undue spread of the coating material.

5. In a machine for coating the projecting back seams of shoe uppers, a supporting post having a front-to-back seam-receiving groove at its upper end, a passage opening into said groove through which coating material may be extruded onto the seam, and a depressible gate slidably mounted on the machine for up-anddown movement at the front of the groove, said gate being resiliently supported whereby it may be moved out of the way by the pressure of the work while acting to dam one end of the groove when no work is being presented.

6. In a machine for coating the projecting back-seam ribs of shoe uppers, a supporting post having a front-to-back seam-receiving and guiding groove at its upper end, and having a passage opening into said groove through which coating material may be extruded onto the seam, said groove being widened only in the neighborhood of said opening to allow a coating of the sides of the seam rib, and a feed roll for moving an upper over said post.

'7. In a machine for coating the back-seam ribs of shoe uppers, a work-supporting post having at its upper end a transversely extending ribfitting groove, means for extruding thermoactive material into said groove to coat the seam of an upper in a right-side-out position thereon, a treadle-operated valve controlling said extruding means, a receptacle for a supply of material, means for heating the coating material in the receptacle, a spreader arranged adjacent to the far end of the rib-receiving groove, means for moving the work toward said spreader, and means for maintaining the temperature of such spreader substantially higher than the temperature imparted to the post by the cement.

'8. A machine as in claim 7 in which a major portion of the spreader body is spaced from the post.

9. In a machine for coating the back seams of shoe uppers, a post for supporting the rear end of a shoe upper in right-side-out condition, said post having a seam-receiving groove provided with an outlet opening, means for supplying thermoactive material to said outlet opening, a grooved gate positioned at the work-entering end of the groove with the bottom of its groove higher than the bottom of the groove in the post, a grooved spreader positioned at the leaving end of the groove, and means for moving the work in the direction of the grooves from post to spreader.

10. A machine as in claim 9 in which the grooved gate at the entering end is movably mounted on the post so that it is depressible by the work.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,391,281 Snyder Sept. 20, 1921 1,968,897 Meader Aug, '7, 1934 2,189,738 Miller Feb. 6, 1940 

